In the present computer technology the use of e-mail is very common. An e-mail service user often receives more than ten e-mail messages per day. Some users receive more than a hundred of e-mail messages per day.
Generally when composing an e-mail message a sender fills in a subject field where s(he) can provide a brief summary of a topic of the e-mail message. The “subject” field allows the user to familiarize her (him)self with a pack of received e-mail messages and immediately upon receiving an e-mail message define its priority. For example the user can immediately realize that the message with the “subject” field “Biggest-ever discount on suitcases!” is of minor importance without reading its content. and, on the contrary, determine that the message with the “subject” field “Important notice: Your flight details have changed” as important.
In some cases however the “subject” field can be insufficient for determining priority of the e-mail message. It happens when an author suggested an indistinct topic or when the user receives a lot of e-mail messages with similar topics. In such cases a function of a preview the first lines of an e-mail message can be useful. For example, Microsoft Outlook™ e-mail client allows to review the first three lines of a message in the main window.
In some cases reviewing some of the first lines does not allow to determine priority of the e-mail message either. For example, it happens when the first lines comprise a title and general introduction phrases. Such insignificant words and phrases can hide the main point of the message.
Thus, although the conventional computer systems are decent, the improvement of these systems is still possible.